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Vedhanayagam M, Andra S, Muthalagu M, Janardhanan Sreeram K. Influence of Functionalized Gold Nanorods on the Structure of Cytochrome –C: An Effective Bio-nanoconjugate for Biomedical Applications. INORG CHEM COMMUN 2022. [DOI: 10.1016/j.inoche.2022.110182] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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Kim G, Kim J, Kim SM, Kato T, Yoon J, Noh S, Park EY, Park C, Lee T, Choi JW. Fabrication of MERS-nanovesicle biosensor composed of multi-functional DNA aptamer/graphene-MoS 2 nanocomposite based on electrochemical and surface-enhanced Raman spectroscopy. SENSORS AND ACTUATORS. B, CHEMICAL 2022; 352:131060. [PMID: 34785863 PMCID: PMC8582077 DOI: 10.1016/j.snb.2021.131060] [Citation(s) in RCA: 26] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/10/2021] [Revised: 10/29/2021] [Accepted: 11/02/2021] [Indexed: 05/09/2023]
Abstract
Middle East respiratory syndrome coronavirus (MERS-CoV) is one of the most harmful viruses for humans in nowadays. To prevent the spread of MERS-CoV, a valid detection method is highly needed. For the first time, a MERS-nanovesicle (NV) biosensor composed of multi-functional DNA aptamer and graphene oxide encapsulated molybdenum disulfide (GO-MoS2) hybrid nanocomposite was fabricated based on electrochemical (EC) and surface-enhanced Raman spectroscopy (SERS) techniques. The MERS-NV aptamer was designed for specifically binding to the spike protein on MERS-NVs and it is prepared using the systematic evolution of ligands by exponential enrichment (SELEX) technique. For constructing a multi-functional MERS aptamer (MF-aptamer), the prepared aptamer was connected to the DNA 3-way junction (3WJ) structure. DNA 3WJ has the three arms that can connect the three individual functional groups including MERS aptamer (bioprobe), methylene blue (signal reporter) and thiol group (linker) Then, GO-MoS2 hybrid nanocomposite was prepared for the substrate of EC/SERS-based MERS-NV biosensor construction. Then, the assembled multifunctional (MF) DNA aptamer was immobilized on GO-MoS2. The proposed biosensor can detect MERS-NVs not only in a phosphate-buffered saline (PBS) solution (SERS LOD: 0.176 pg/ml, EIS LOD: 0.405 pg/ml) but also in diluted 10% saliva (SERS LOD: 0.525 pg/ml, EIS LOD: 0.645 pg/ml).
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Affiliation(s)
- Gahyeon Kim
- Department of Chemical Engineering, Kwangwoon University, 20 Kwangwoon-Ro, Nowon-Gu, Seoul 01897, Republic of Korea
| | - Jinmyeong Kim
- Department of Chemical Engineering, Kwangwoon University, 20 Kwangwoon-Ro, Nowon-Gu, Seoul 01897, Republic of Korea
| | - Soo Min Kim
- Department of Chemical Engineering, Kwangwoon University, 20 Kwangwoon-Ro, Nowon-Gu, Seoul 01897, Republic of Korea
| | - Tatsuya Kato
- Green Chemistry Research Division, Research Institute of Green Science and Technology Shizuoka University, Ohya 836, Suruga-ku, Shizuoka, Japan
| | - Jinho Yoon
- Department of Chemical & Biomolecular Engineering, Sogang University, Baekbeom-Ro, Mapo-Gu, Seoul 04107, Republic of Korea
| | - Seungwoo Noh
- Department of Chemical Engineering, Kwangwoon University, 20 Kwangwoon-Ro, Nowon-Gu, Seoul 01897, Republic of Korea
| | - Enoch Y Park
- Green Chemistry Research Division, Research Institute of Green Science and Technology Shizuoka University, Ohya 836, Suruga-ku, Shizuoka, Japan
| | - Chulhwan Park
- Department of Chemical Engineering, Kwangwoon University, 20 Kwangwoon-Ro, Nowon-Gu, Seoul 01897, Republic of Korea
| | - Taek Lee
- Department of Chemical Engineering, Kwangwoon University, 20 Kwangwoon-Ro, Nowon-Gu, Seoul 01897, Republic of Korea
| | - Jeong-Woo Choi
- Department of Chemical & Biomolecular Engineering, Sogang University, Baekbeom-Ro, Mapo-Gu, Seoul 04107, Republic of Korea
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da Silva RTP, Ribeiro de Barros H, Sandrini DMF, Córdoba de Torresi SI. Stimuli-Responsive Regulation of Biocatalysis through Metallic Nanoparticle Interaction. Bioconjug Chem 2022; 33:53-66. [PMID: 34914373 DOI: 10.1021/acs.bioconjchem.1c00515] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
The remote control of biocatalytic processes in an extracellular medium is an exciting idea to deliver innovative solutions in the biocatalysis field. With this purpose, metallic nanoparticles (NPs) are great candidates, as their inherent thermal, electric, magnetic, and plasmonic properties can readily be manipulated upon external stimuli. Exploring the unique NP properties beyond an anchoring platform for enzymes brings up the opportunity to extend the efficiency of biocatalysts and modulate their activity through triggered events. In this review, we discuss a set of external stimuli, such as light, electricity, magnetism, and temperature, as tools for the regulation of nanobiocatalysis, including the challenges and perspectives regarding their use. In addition, we elaborate on the use of combined stimuli that create a more refined framework in terms of a multiresponsive system. Finally, we envision this review might instigate researchers in this field of study with a set of promising opportunities in the near future.
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Affiliation(s)
- Rafael T P da Silva
- Instituto de Química, Universidade de São Paulo, São Paulo (SP), 05508-000, Brazil
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Modenez IA, Macedo LJA, Melo AFAA, Pereira AR, Oliveira ON, Crespilho FN. Nanosized non-proteinaceous complexes III and IV mimicking electron transfer of mitochondrial respiratory chain. J Colloid Interface Sci 2021; 599:198-206. [PMID: 33945968 DOI: 10.1016/j.jcis.2021.04.072] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2021] [Revised: 03/24/2021] [Accepted: 04/13/2021] [Indexed: 11/25/2022]
Abstract
Synthetic biology pursues the understanding of biological processes and their possible mimicry with artificial bioinspired materials. A number of materials have already been used to mimic the active site of simple redox proteins, including nanosized iron oxides due to their redox properties. However, the mimicry of membrane redox protein complexes is still a challenge. Herein, magnetic iron oxide nanoparticles (NPs), incorporated as non-proteinaceous complexes III and IV in a mitochondrial model membrane, catalyze electron transfer (ET) similarly to the natural complexes towards cytochrome c. The associated molecular mechanism is experimentally proven in solution and in a Langmuir-Blodgett film. A direct and entropy-driven ET, with rate constant of 2.63 ± 0.05Lmol-1 at 25 °C, occurs between the iron sites of the NPs and the cytochrome c heme group, not affecting the protein secondary and tertiary structures. This process requires an activation energy of 40.2 ± 1.5 kJ mol-1 resulting in an overall Gibbs free energy of -55.3 kJ mol-1. Furthermore, the protein-NP system is governed by electrostatic and non-polar forces that contribute to an associative mechanism in the transition state. Finally, the incorporated NPs in a model membrane were able to catalyze ET, such as the natural complexes in respiratory chain. This work presents an experimental approach demonstrating that inorganic nanostructured systems may behave as embedded proteins in the eukaryotic cells membrane, opening the way for more sophisticated and robust mimicry of membrane protein complexes.
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Affiliation(s)
- Iago A Modenez
- São Carlos Institute of Chemistry, University of São Paulo, São Carlos 13560-970, Brazil
| | - Lucyano J A Macedo
- São Carlos Institute of Chemistry, University of São Paulo, São Carlos 13560-970, Brazil
| | - Antonio F A A Melo
- São Carlos Institute of Chemistry, University of São Paulo, São Carlos 13560-970, Brazil; Materials Engineering Graduate Program, Federal Institute of Education, Science and Technology of Piauí, Central Campus, Teresina 64000-040, PI, Brazil
| | - Andressa R Pereira
- São Carlos Institute of Physics, University of São Paulo, São Carlos 13560-590, Brazil
| | - Osvaldo N Oliveira
- São Carlos Institute of Physics, University of São Paulo, São Carlos 13560-590, Brazil
| | - Frank N Crespilho
- São Carlos Institute of Chemistry, University of São Paulo, São Carlos 13560-970, Brazil.
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Shahabadi N, Zendehcheshm S, Khademi F. Selenium nanoparticles: Synthesis, in-vitro cytotoxicity, antioxidant activity and interaction studies with ct-DNA and HSA, HHb and Cyt c serum proteins. ACTA ACUST UNITED AC 2021; 30:e00615. [PMID: 33948440 PMCID: PMC8080047 DOI: 10.1016/j.btre.2021.e00615] [Citation(s) in RCA: 31] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2020] [Revised: 03/29/2021] [Accepted: 04/06/2021] [Indexed: 12/18/2022]
Abstract
Spherical SeNPs with average size 134 nm were synthesized employing Vitamin C. The synthesized SeNPs represented great antioxidant and anticancer activity. The interaction of SeNPs with ct-DNA, HSA, HHb and Cyt c was investigated. Nano-selenium can bind to ct-DNA through partial intercalation binding mode. HSA, HHb and Cyt c could keep their biological activity even in the presence of Nano-selenium.
The aim of this study was the synthesis of selenium nanoparticles (SeNPs) employing vitamin C as a biocompatible and low toxic reducing agent. The synthesized selenium nanoparticles were characterized by using UV–vis, FT-IR, SEM-EDX, TEM, DLS, and zeta potential measurements. The results of the DPPH free radical scavenging assay demonstrate that this synthesized nano-selenium has strong potentials to scavenge the free radicals and cytotoxicity against MCF-7 and Raji Burkitt's lymphoma cancer cell lines. The interaction of calf thymus DNA (ct-DNA) with SeNPs indicated that the anticancer activity might be associated with the DNA-binding properties of nano-selenium. Finally, it was found that the synthesized nano-selenium can bind to the most important blood proteins such as human serum albumin (HSA), human hemoglobin (HHb), and Cytochrome c (Cyt c). The results showed that the secondary structure of these proteins remains unchanged, suggesting that the synthesized nano-selenium could be employed as a carrier in the drug delivery system without any cytotoxicity effect.
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Affiliation(s)
- Nahid Shahabadi
- Department of Inorganic Chemistry, Faculty of Chemistry, Razi University, Kermanshah, Iran.,Center of Medical Biology Research (MBRC) Kermanshah University of Medical Sciences, Kermanshah, Iran
| | - Saba Zendehcheshm
- Department of Inorganic Chemistry, Faculty of Chemistry, Razi University, Kermanshah, Iran.,Center of Medical Biology Research (MBRC) Kermanshah University of Medical Sciences, Kermanshah, Iran
| | - Fatemeh Khademi
- Center of Medical Biology Research, Health Technology Institute, Kermanshah University of Medical Sciences, Kermanshah, Iran
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Mattioli IA, Hassan A, Oliveira ON, Crespilho FN. On the Challenges for the Diagnosis of SARS-CoV-2 Based on a Review of Current Methodologies. ACS Sens 2020; 5:3655-3677. [PMID: 33267587 PMCID: PMC7724986 DOI: 10.1021/acssensors.0c01382] [Citation(s) in RCA: 55] [Impact Index Per Article: 13.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2020] [Accepted: 11/17/2020] [Indexed: 12/13/2022]
Abstract
Diagnosis of COVID-19 has been challenging owing to the need for mass testing and for combining distinct types of detection to cover the different stages of the infection. In this review, we have surveyed the most used methodologies for diagnosis of COVID-19, which can be basically categorized into genetic-material detection and immunoassays. Detection of genetic material with real-time polymerase chain reaction (RT-PCR) and similar techniques has been achieved with high accuracy, but these methods are expensive and require time-consuming protocols which are not widely available, especially in less developed countries. Immunoassays for detecting a few antibodies, on the other hand, have been used for rapid, less expensive tests, but their accuracy in diagnosing infected individuals has been limited. We have therefore discussed the strengths and limitations of all of these methodologies, particularly in light of the required combination of tests owing to the long incubation periods. We identified the bottlenecks that prevented mass testing in many countries, and proposed strategies for further action, which are mostly associated with materials science and chemistry. Of special relevance are the methodologies which can be integrated into point-of-care (POC) devices and the use of artificial intelligence that do not require products from a well-developed biotech industry.
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Affiliation(s)
- Isabela A. Mattioli
- São Carlos Institute of
Chemistry, University of São Paulo,
São Carlos 13560-970, São Paulo,
Brazil
| | - Ayaz Hassan
- São Carlos Institute of
Chemistry, University of São Paulo,
São Carlos 13560-970, São Paulo,
Brazil
| | - Osvaldo N. Oliveira
- São Carlos Institute of
Physics, University of São Paulo,
São Carlos 13560-590, São Paulo,
Brazil
| | - Frank N. Crespilho
- São Carlos Institute of
Chemistry, University of São Paulo,
São Carlos 13560-970, São Paulo,
Brazil
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Kumar V, Sachdev A, Matai I. Self-assembled reduced graphene oxide–cerium oxide nanocomposite@cytochrome chydrogel as a solid electrochemical reactive oxygen species detection platform. NEW J CHEM 2020. [DOI: 10.1039/d0nj02038a] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
A new dimension for the selective detection of short-lived ROS by an electroactive reduced graphene oxide–cerium oxide nanocomposite@cytochromechydrogel.
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Affiliation(s)
- Vijayesh Kumar
- CSIR-Central Scientific Instruments Organization (CSIR-CSIO)
- Chandigarh-160030
- India
| | - Abhay Sachdev
- CSIR-Central Scientific Instruments Organization (CSIR-CSIO)
- Chandigarh-160030
- India
- Academy of Scientific and Innovative Research (AcSIR-CSIO)
- Chandigarh
| | - Ishita Matai
- CSIR-Central Scientific Instruments Organization (CSIR-CSIO)
- Chandigarh-160030
- India
- Academy of Scientific and Innovative Research (AcSIR-CSIO)
- Chandigarh
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Melo AFAA, Sedenho GC, Osica I, Ariga K, Crespilho FN. Electrochemical Behavior of Cytochrome C Immobilized in a Magnetically Induced Mesoporous Framework. ChemElectroChem 2019. [DOI: 10.1002/celc.201901047] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Affiliation(s)
- Antonio F. A. A. Melo
- São Carlos Institute of Chemistry (IQSC)University of São Paulo (USP) 13560-970 São Carlos, SP Brazil
- Federal Institute of EducationScience and Technology of Piauí 64000-040 Teresina, PI Brazil
- World Premier International (WPI) Research Center for Materials Nanoarchitectonics (MANA)NationalInstitute for Materials Science (NIMS) 1-1 Namiki Tsukuba 305-0044 Japan
| | - Graziela C. Sedenho
- São Carlos Institute of Chemistry (IQSC)University of São Paulo (USP) 13560-970 São Carlos, SP Brazil
| | - Izabela Osica
- World Premier International (WPI) Research Center for Materials Nanoarchitectonics (MANA)NationalInstitute for Materials Science (NIMS) 1-1 Namiki Tsukuba 305-0044 Japan
- Faculty of Materials Science and EngineeringWarsaw University of Technology Woloska 141 02-507 Warsaw Poland
| | - Katsuhiko Ariga
- World Premier International (WPI) Research Center for Materials Nanoarchitectonics (MANA)NationalInstitute for Materials Science (NIMS) 1-1 Namiki Tsukuba 305-0044 Japan
- Department of Advanced Materials Science Graduate School of Frontier SciencesThe University of Tokyo 5-1-5 Kashiwanoha, Kashiwa Chiba 277-8561 Japan
| | - Frank N. Crespilho
- São Carlos Institute of Chemistry (IQSC)University of São Paulo (USP) 13560-970 São Carlos, SP Brazil
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Spectroscopic approach for the interaction of carbon nanoparticles with cytochrome c and BY-2 cells: Protein structure and mitochondrial function. Int J Biol Macromol 2019; 138:29-36. [PMID: 31302123 DOI: 10.1016/j.ijbiomac.2019.07.076] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2019] [Revised: 07/10/2019] [Accepted: 07/10/2019] [Indexed: 12/24/2022]
Abstract
In this study, we employed multiple spectroscopic methods to analyze the effects of carbon nanoparticles (CNPs) on structure of cytochrome c (Cyt c) and mitochondrial function in plant cells. The tertiary structures of aromatic amino acid in Cyt c were not changed after addition of CNPs. Cyt c was found to be absorbed on the surfaces of CNPs in a non-linear manner and only bound Cyt c can be reduced. In addition, the binding of Cyt c was found to increase the diameter of CNPs at lower concentrations. The redox potential of Cyt c was almost not affected after treatment with CNPs. There were no obvious differences in cellular ATP after exposure to CNPs, and the mitochondrial membrane potential (MMP) was significantly decreased once the CNPs concentration exceeded 31.25 μg/mL. The levels of reactive oxygen species (ROS) also were increased in BY-2 cells. Taken together, these findings provide basis for the interactions between CNPs and Cyt c, as well as the effect of CNPs treatment on the mitochondria function in plant cells.
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Melo AFAA, Hassan A, Macedo LJA, Osica I, Shrestha LK, Ji Q, Oliveira ON, Henzie J, Ariga K, Crespilho FN. Microwires of Au-Ag Nanocages Patterned via Magnetic Nanoadhesives for Investigating Proteins using Surface Enhanced Infrared Absorption Spectroscopy. ACS APPLIED MATERIALS & INTERFACES 2019; 11:18053-18061. [PMID: 30964981 DOI: 10.1021/acsami.8b21815] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
The controlled assembly of metal nanoparticles into ordered structures interacting with biological molecules is an emerging concept in surface science. Here, bare magnetite nanoparticles (Fe3O4-NPs) were employed as nanoadhesives to capture hollow metallic nanostructures (Au-Ag nanocages) from aqueous suspensions, and these coupled nanostructures were patterned onto various types of substrate via magnetolithography. Microwires of Au-Ag nanocages patterned onto an Au substrate behaved as optical antennas, providing a plasmonic enhancement exploited in surface-enhanced infrared absorption spectroscopy (SEIRAS) to investigate the proteins cytochrome c, bilirubin oxidase, alcohol dehydrogenase, bovine serum albumin, and glucose oxidase. Chemical maps containing more than 4000 spectra, acquired within only 2 min with a focal plane array detector, indicate that proteins were adsorbed along the microwires with their secondary structure preserved according to the spatial distribution of their amide groups. We believe there are significant practical aspects of the methodology proposed here to develop an alternative label-free assay for investigating biological molecules.
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Affiliation(s)
- Antonio F A A Melo
- São Carlos Institute of Chemistry , University of São Paulo , São Carlos 13560-970 , São Paulo , Brazil
- World Premier International (WPI) Research Center for Materials Nanoarchitectonics (MANA) , National Institute for Materials Science (NIMS) , 1-1 Namiki , Tsukuba 305-0044 , Japan
| | - Ayaz Hassan
- São Carlos Institute of Chemistry , University of São Paulo , São Carlos 13560-970 , São Paulo , Brazil
| | - Lucyano J A Macedo
- São Carlos Institute of Chemistry , University of São Paulo , São Carlos 13560-970 , São Paulo , Brazil
| | - Izabela Osica
- World Premier International (WPI) Research Center for Materials Nanoarchitectonics (MANA) , National Institute for Materials Science (NIMS) , 1-1 Namiki , Tsukuba 305-0044 , Japan
- Faculty of Materials Science and Engineering , Warsaw University of Technology , Woloska 141 , Warsaw 02-507 , Poland
| | - Lok Kumar Shrestha
- World Premier International (WPI) Research Center for Materials Nanoarchitectonics (MANA) , National Institute for Materials Science (NIMS) , 1-1 Namiki , Tsukuba 305-0044 , Japan
| | - Qingmin Ji
- World Premier International (WPI) Research Center for Materials Nanoarchitectonics (MANA) , National Institute for Materials Science (NIMS) , 1-1 Namiki , Tsukuba 305-0044 , Japan
| | - Osvaldo N Oliveira
- São Carlos Institute of Physics , University of São Paulo , São Carlos 13566-590 , São Paulo Brazil
| | - Joel Henzie
- World Premier International (WPI) Research Center for Materials Nanoarchitectonics (MANA) , National Institute for Materials Science (NIMS) , 1-1 Namiki , Tsukuba 305-0044 , Japan
| | - Katsuhiko Ariga
- World Premier International (WPI) Research Center for Materials Nanoarchitectonics (MANA) , National Institute for Materials Science (NIMS) , 1-1 Namiki , Tsukuba 305-0044 , Japan
- Department of Advanced Materials Science, Graduate School of Frontier Sciences , The University of Tokyo , 5-1-5 Kashiwanoha , Kashiwa , Chiba 277-8561 , Japan
| | - Frank N Crespilho
- São Carlos Institute of Chemistry , University of São Paulo , São Carlos 13560-970 , São Paulo , Brazil
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Lee T, Lee Y, Park SY, Hong K, Kim Y, Park C, Chung YH, Lee MH, Min J. Fabrication of electrochemical biosensor composed of multi-functional DNA structure/Au nanospike on micro-gap/PCB system for detecting troponin I in human serum. Colloids Surf B Biointerfaces 2019; 175:343-350. [DOI: 10.1016/j.colsurfb.2018.11.078] [Citation(s) in RCA: 41] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2018] [Revised: 11/15/2018] [Accepted: 11/28/2018] [Indexed: 12/01/2022]
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PEREIRA ANDRESSAR, SEDENHO GRAZIELAC, SOUZA JOÃOCPDE, CRESPILHO FRANKN. Advances in enzyme bioelectrochemistry. ACTA ACUST UNITED AC 2018; 90:825-857. [DOI: 10.1590/0001-3765201820170514] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2017] [Accepted: 10/11/2017] [Indexed: 11/21/2022]
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Abstract
Extensive simulations of cytochrome c in solution are performed to address the apparent contradiction between large reorganization energies of protein electron transfer typically reported by atomistic simulations and much smaller values produced by protein electrochemistry. The two sets of data are reconciled by deriving the activation barrier for electrochemical reaction in terms of an effective reorganization energy composed of half the Stokes shift (characterizing the medium polarization in response to electron transfer) and the variance reorganization energy (characterizing the breadth of electrostatic fluctuations). This effective reorganization energy is much smaller than each of the two components contributing to it and is fully consistent with electrochemical measurements. Calculations in the range of temperatures between 280 and 360 K combine long, classical molecular dynamics simulations with quantum calculations of the protein active site. The results agree with the Arrhenius plots for the reaction rates and with cyclic voltammetry of cytochrome c immobilized on self-assembled monolayers. Small effective reorganization energy, and the resulting small activation barrier, is a general phenomenology of protein electron transfer allowing fast electron transport within biological energy chains.
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Affiliation(s)
- Salman S Seyedi
- Department of Physics, Arizona State University , P.O. Box 871504, Tempe, Arizona 85287-1504, United States
| | - Morteza M Waskasi
- School of Molecular Sciences, Arizona State University , P.O. Box 871604, Tempe, Arizona 85287-1604, United States
| | - Dmitry V Matyushov
- Department of Physics, Arizona State University , P.O. Box 871504, Tempe, Arizona 85287-1504, United States.,School of Molecular Sciences, Arizona State University , P.O. Box 871604, Tempe, Arizona 85287-1604, United States
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